Method of and means for annealing steel.



UNITED STATES PATENT OFFICE.

JAMES GEORGE RAPID MUN DAY, OF KINGSTON-UPON-HULL, ENGLAND..

METHOD OF AND MEANS FOR ANNEALING STEEL.

No Drawing.

To all whom it may concern:

vBe it known that I, JAMES GEORGE RAPID MUNDAY, a subject of the King of Great Britain, residing at Kingston upon-Hull, England, have invented certain new and useful Improvements in Methods of and Means for Annealing Steel, of which the following is a specificatlon.

This invention relates to a novel or improved method of and, means for annealing steel whereby articles made of steel, and especially those made of what is known as high-speed or air-hardened steel can be annealed at much less expense and in considerably less time than heretofore.

The practice usually followed in annealing articles of steel, consists in placing the articles in a chamber heated nearly to redness in which they are allowed to cool very slowly with the result that all the particles of the steel cool and contract at the same rate.

This process is not only a somewhat costly one as a result of the cost of the chamber and the expense of heating it, but it is a slow one, as large articles may take as long as a fortnight before being completely annealed, smaller articles taking from six to sixty hours, according to their thickness and weight.

The present invention has for its object, to dispense with an expensive chamber and the cost of heating the same, and to simplify the process of and considerably reduce the time occupied in the annealing of steel articles.

My invention consists of a combination of certain ingredients which when mixed to gether form a liquid which by the steel articles being placed in it causes perfect annealing of the same in an extremely short time, my annealing liquid or mixture dispensing with the necessity for allowing the steel after being heated, to cool gradually.

To produce my annealing liquid or mixture I employ turpentine, resin and common salt in suitable proportions, the proportions of these ingredients being say, approximately, to produce a small quantity of the mixture, one gallon of turpentine, four pounds by weight of resin and two pounds by weight, or thereabouts, of salt.

Mixing of the ingredients is eflected in a suitable vessel, the resin being according to a convenient mode, first melted and the tureqpi s of t is patent may be obtained t Specification of Letters Patent.

Patented Aug. 2'7, 1918.

Application filed August 6, 1917. Serial 0. 184,658.

pentine and salt then added thereto, the ingredients being maintained at a suitable heat by supplying heat to the vessel during which time they are thoroughly mixed by stirring them, or by other suitable means. After thorough mixing of the ingredients has been effected, the mixture is allowed to cool and when cool or cold is ready for use.

While a mixture of turpentine and resin in suitable proportions will produce equally as satisfactory results so'far as the actual annealing of the metal is concerned, without the addition of salt, I prefer to add salt to;

the two ingredients mentioned as it has the effect of softening the skin or outer surface of the steel, and also for the reason that it reduces the infiammability of the turpentine of my mixture, the steel is first heated to a temperature of preferably between 600 and 700 degrees centigrade and is then placed in the annealing mixture and allowed to remain therein until cool or cold, by'which time it has become effectually annealed.

In annealing other kinds of steel, the steel is preferably heated until it becomes a blood red, after which, to obtain the best results, the color is allowed to run off and the article is placed in the annealing mixture and allowed to remain therein until cool or cold by which time it is effectually annealed.

I claim:

1. A method of annealing high-speed steel, which consists in heating the steel to a temperature of between 600 and 700 degrees, centigrade, and then placing it in a mixture comprising turpentine and resin an permitting it to cool therein.

2. A mixture for use in annealing highspeed steel, comprising turpentine and resin,

" In testimony whereof I affix mysignature in presence of two witnesses. V

, JAMES GEORGE RAPID MUNDAY.

, Witnesses:

LOUIS E. KIPPAX, HERBERT WHEAT.

five cents each, by addressing the Gemstone; or retest. wemgt aa 

